Ice and fire forge a reservoir for life on Mars

Braided fluvial channels (inset) emerge from the edge of glacial deposits roughly 210 million years old on the martian volcano Arsia Mons, nearly twice as high as Mount Everest. (Colors indicate elevation.) Credit: NASA/Goddard Space Flight Center/Arizona State University/Brown University


                                               Where volcanoes meet glaciers, lakes often form. This happens in many places on Earth and in at least one place off it: Arsia Mons, Mars.
Arsia Monsis one of the largest mountains in the solar system. Wispy water-ice clouds gather near its peak during the Martian afternoon. While it is only the third tallest volcano on Mars, Arsia Mons is 300 km (186 miles) wide and twice as tall as Mount Everest. If Mount Everest were to suddenly erupt today, some of the vast glaciers on its surface would melt producing floods, lakes and debris plains. We now have reason to believe this is exactly what happened on Mars when Arsia Mons was active 200 million years ago.
The evidence for these events lies along the northwest flank of the volcano. Fan-shaped-deposits (FSDs) seen by the Mars Reconnaissance Orbiter bear a striking resemblance to alluvial deposits. Such deposits are found on Earth in Death Valley, in the mountains of France, and in many places prone to flash-flooding or glacial melting. In 2012, the Mars Curiosity rover found fluvial deposits in the Gale crater. In a recently published study Kathleen Scanlon and her colleagues at Brown, Boston University, and Lancaster University in the UK showed how the FSDs and other geologic features seen near Arsia Mons are best explained by glacial deposits and enormous quantities of water.
"The term 'fan shaped deposit' usually refers to the whole glacial deposit, which was mostly created by ice that was frozen to its bed," said Scanlon, "While we think all the glaciovolcanic edifices in the FSD had englacial lakes surrounding them, the outflow channels at the northwestern edge of the deposit are the only evidence we have for the flow, per se, of large quantities of water here."

Read more at: http://phys.org/news/2014-06-ice-forge-reservoir-life-mars.html#jCp

Researchers discover how a cluster of water molecules adapts to the presence of an extra proton

H2O is the molecule everybody knows, and nobody can live without. But for all its familiarity and import for life, aspects of water's behavior have been hard to pin down, including how it conducts positive charge.

In the current issue of the journal Science, Yale University chemists report tracing how a cluster of water molecules adapts to the presence of an extra proton, the positively charged subatomic particle.

Water constantly encounters stray protons—in biological contexts, as when light impinges on the eye's retina, for example, or in purely chemical contexts, as when water is split by electrolysis, or in technological contexts, as in the operation of fuel cells.

The new research results provide long-sought experimental data that advance understanding of water's ability to conduct charge, and researchers expect the data to help theoretical chemists simulate how positive charge propagates through a more extended three-dimensional water network. This in turn will shed light on the way positive charge moves in biological systems.



"Getting this right is one of the grand challenges of contemporary physical chemistry research, and we believe we've taken a big step," said Yale chemist Mark Johnson, the lead investigator. "We now have a clear picture of how an extra proton effectively 'hides' in a three-dimensional water network, solving a decade-long mystery raised by earlier work that revealed everything except the lair of that critical proton."

Scientists have long known and understood how water conducts negative charge (electrons). But showing how positive charge moves through water has been difficult because water molecules are not spectators in the process, Johnson said, but rather "are in fact intrinsic to the effect."

Read more at: http://phys.org/news/2014-06-cluster-molecules-presence-extra-proton.html#jCp

NRC human spaceflight report says NASA strategy can’t get humans to Mars

A sweeping review of NASA’s human spaceflight program has concluded that the agency has an unsustainable and unsafe strategy that will prevent the United States from achieving a human landing on Mars in the foreseeable future.

The 286-page National Research Council report, the culmination of an 18-month, $3.2 million investigation mandated by Congress, says that to continue on the present course under budgets that don’t keep pace with inflation “is to invite failure, disillusionment, and the loss of the longstanding international perception that human spaceflight is something the United States does best.”

The report makes a case for sending astronauts back to the moon. That had been a key element of NASA’s strategy under President George W. Bush. But President Obama and his advisers explicitly opposed another moon landing (“I just have to say pretty bluntly here: We’ve been there before,” Obama said in a speech on space policy in 2010).

A major argument against returning to the moon was that it didn’t pencil out — that there wasn’t nearly enough money dedicated to the program. Now the NRC’s Committee on Human Spaceflight has come to the same conclusion about the Obama administration’s vision for NASA. If the goal is a human landing on Mars, the current strategy won’t work.

“Absent a very fundamental change in the nation’s way of doing business, it is not realistic to believe that we can achieve the consensus goal of reaching Mars,” Mitch Daniels, the former Indiana governor and co-chair of the committee, said Wednesday morning in an interview.


http://www.washingtonpost.com/national/health-science/nrc-human-spaceflight-report-says-nasa-strategy-cant-get-humans-to-mars/2014/06/04/e6e6060c-ebd6-11e3-9f5c-9075d5508f0a_story.html

New isotopic evidence supporting moon formation via Earth collision with planet-sized body

Thin section of an enstatite chondrite fragment from the asteroid Almahatta Sitta (official name: 2008 TC3). This fragment was observed on 7 October 2008 in the Nubian Desert, Sudan. Credit: Addi Bischoff, Westfälische Wilhelms-Universität Münster

A new series of measurements of oxygen isotopes provides increasing evidence that the Moon formed from the collision of the Earth with another large, planet-sized astronomical body, around 4.5 billion years ago. This work will be published in Science on June 6, and will be presented to the Goldschmidt geochemistry conference in California on 11th June.

Most planetary scientists believe that the Moon formed from an impact between the Earth and a planet-sized body, which has been given the name Theia. Efforts to confirm that the impact had taken place had centred on measuring the ratios between the isotopes of oxygen, titanium, silicon and others. These ratios are known to vary throughout the solar system, but their close similarity between Earth and Moon conflicted with theoretical models of the collision that indicated that the Moon would form mostly from Theia, and thus would be expected to be compositionally different from the Earth.

Read more at: http://phys.org/news/2014-06-isotopic-evidence-moon-formation-earth.html#jCp

MIT lab designs workload-sharing robotic limbs (w/ Video)

Mention "robotic limbs" and one thinks of devices being developed to replace the loss of human limbs. Mention "exoskeleton" and one thinks of a suit governing and bound to the entire body. Researchers at the d'Arbeloff Laboratory for Information Systems and Technology at MIT, led by Professor Harry Asada, Ford Professor of Engineering, have been breaking ground in another direction. They are working in a co-robot world, and they are developing "extras" for what the person already has. Videos showing people performing tasks tell a story of what future work might look like when an extra set of arms or legs will be of significant help. "Supernumerary Robotic Limbs" (SRLs) is the formal term to describe robotic limbs that, when worn, augment limbs already in place.

"Imagine that one day humans will have a third arm and a third leg attached to their body. The extra limbs will help them hold objects, support the human body, share a workload, and streamline the execution of a task. If the movements of such supernumerary limbs are tightly coupled and coordinated with their arms, the human users may come to perceive the extra limbs as an extension of their own body," the Lab team suggest on their site. "The goal of our work is to build a co-robot that becomes a functional extension of the human body."

In such settings, the extra arm or leg attached to the body helps to hold objects, share workloads, and streamline tasks......


Read more at: http://phys.org/news/2014-06-mit-lab-workload-sharing-robotic-limbs.html#jCp

A first for NASA's IRIS: Observing a gigantic eruption of solar material

A coronal mass ejection, or CME, surged off the side of the sun on May 9, 2014, and NASA's newest solar observatory caught it in extraordinary detail. This was the first CME observed by the Interface Region Imaging Spectrograph, or IRIS, which launched in June 2013 to peer into the lowest levels of the sun's atmosphere with better resolution than ever before. Watch the movie to see how a curtain of solar material erupts outward at speeds of 1.5 million miles per hour.

IRIS must commit to pointing at certain areas of the sun at least a day in advance, so catching a CME in the act involves some educated guesses and a little bit of luck.

"We focus in on active regions to try to see a flare or a CME," said Bart De Pontieu, the IRIS science lead at Lockheed Martin Solar & Astrophysics Laboratory in Palo Alto, California. "And then we wait and hope that we'll catch something. This is the first clear CME for IRIS so the team is very excited."

The IRIS imagery focuses in on material of 30,000 kelvins at the base, or foot points, of the CME. The line moving across the middle of the movie is the entrance slit for IRIS's spectrograph,....


Read more at: http://phys.org/news/2014-05-nasa-iris-gigantic-eruption-solar.html#jCp

Anti-diabetic drug metformin slows aging and lengthens lifespan

A study by Belgian doctoral researcher Wouter De Haes (KU Leuven) and colleagues provides new evidence that metformin, the world's most widely used anti-diabetic drug, slows ageing and increases lifespan.

 In experiments reported in the journal Proceedings of the National Academy of Sciences, the researchers tease out the mechanism behind metformin's age-slowing effects: the drug causes an increase in the number of toxic oxygen molecules released in the cell and this, surprisingly, increases cell robustness and longevity in the long term.

Mitochondria – the energy factories in cells – generate tiny electric currents to provide the body's cells with energy. Highly reactive oxygen molecules are produced as a by-product of this process.

While these molecules are harmful because they can damage proteins and DNA and disrupt normal cell functioning, a small dose can actually do the cell good, say the researchers: "As long as the amount of harmful oxygen molecules released in the cell remains small, it has a positive long-term effect on the cell. Cells use the reactive oxygen particles to their advantage before they can do any damage," explains Wouter De Haes. "Metformin causes a slight increase in the number of harmful oxygen molecules. We found that this makes cells stronger and extends their healthy lifespan."

It was long thought that harmful reactive oxygen molecules were the very cause of ageing. The food and cosmetics industries are quick to emphasise the 'anti-ageing' qualities of products containing antioxidants, such as skin creams, fruit and vegetable juices, red wine and dark chocolate.

But while antioxidants do in fact neutralise harmful reactive oxygen molecules in the cell, they actually negate metformin's anti-ageing effects because the drug relies entirely on these molecules to work.

The researchers studied metformin's mechanism in the tiny roundworm Caenorhabditis elegans, an ideal species for studying ageing because it has a lifespan of only three weeks. "As they age, the worms get smaller, wrinkle up and become less mobile. But worms treated with metformin show very limited size loss and no wrinkling. They not only age slower, but they also stay healthier longer," says Wouter De Haes. "While we should be careful not to over-extrapolate our findings to humans, the study is promising as a foundation for future research."

Other studies in humans have shown that metformin suppresses some cancers and heart disease. Metformin could even be an effective drug for counteracting the general effects of ageing, say the researchers.


For more details : http://medicalxpress.com/news/2014-06-anti-diabetic-drug-metformin-aging-lengthens.html